Interview with IPCC Chair Rajendra Pachauri

Rajendra K. Pachauri, chair of the Intergovernmental Panel on Climate Change and co-recipient of the 2007 Nobel Peace Prize, has become among the world's most visible, outspoken voices on fighting climate change. Following a speech at the Worldwatch Institute launch of State of the World 2009: Into A Warming World, Dr. Pachauri stepped aside for a conversation with Worldwatch staff writer Ben Block.

Climate scientists have been making more-severe findings over the 14 months since the IPCC Fourth Assessment Report was released in 2007. What do you think has changed since that assessment?

I don't see any changes. I mean, there's always new literature that's coming out, and one should really look at the balance of all the evidence that you get. Certainly a year or two is not a lot, really, for you to come up with a reasoned, objective, and comprehensive assessment of what's happening. We are not in the business of forecasting the weather. We're really projecting climate change.

Based on the lessons you learned from the Fourth Assessment or the events that have transpired since then, how will the next IPCC report be different from previous projects?

One of the things that we're certainly going to focus on is much greater regional [effects]because the impact of climate change has to be essentially studied in the respect of specific locations and regions. Unless we do that, we're only generalizing something that's not factual.

The Fourth Assessment include examples of likely effects in Asia, Africa, and other regions. How will the Fifth Assessment compare?

A great deal depends on the research that's carried out in those locations. One hopes that with all the interest that's been generated on climate change, you get a lot more research out of it in a number of regions in the world that were not covered earlier.

The next report is due to be published in 2014. With many scientists saying that climate change has become more severe since the 2007 assessment, and with the international climate negotiations taking place in Copenhagen this December, do you think a more recent report is needed? 2014 seems like a long time from now.

There's no way you can cut short the process. We have an extremely elaborate procedure designed for a very good reason. It's not easy to go through tens of thousands of pieces of literature and assemble thousands of scientists to come up with a reasonable assessment of what's happening and what's likely to happen. Anything you do in a year or two is going to be suspect. It's not going to be complete. And I don't think it will carry the credibility that a comprehensive assessment of the IPCC actually does.

You don't have an easy job. Is there anyone competing to replace you?

If they do, they're more than welcome.

The IPCC makes estimations on how climate change could be limited to increases of 2 degrees Celsius. How do you feel about this limit - is it too high?

That really has to be seen in relation to what 2 degrees will do to different places of the world. I think Article 2 of the [United Nations Framework Convention on Climate Change], which essentially highlights the need to prevent dangerous anthropogenic interference with the climate system, has to look at "dangerous" in respect to different situations and different regions of the world. You can't have climate science which is uniformly dangerous for the entire world. If you talk to people in locations that are really dangerous, you get response from those people that they are probably close to a state of danger - if they have not already crossed it.

So this whole issue of 2 degrees versus 1 degree or 1.5 degree is something based on a value judgment that essentially relates to what is dangerous, what is a threshold that would define danger in terms of making it almost impossible for some people on this planet not being able to live in those locations. So it's difficult to say if it should be 2 degrees or 1.5 or 1, but this is an issue that needs a great deal of discussion or debate. There's an ethical discussion which should not be ignored at all, and it really hasn't been brought out in the [climate convention] debates.

Have you had a chance to speak with U.S. President-elect Barack Obama?

No... I hope some day in future I get to talk to him.

If Obama were in front of you right now, what would you say?

I would tell him he has the unique opportunity of saving a large part of the human species and several others, because unless the U.S. takes the lead, I'm afraid we will not get an adequate global response. In absence of that, there will obviously be climate change that will go unmitigated. And we're pretty close to the stage where impacts start to turn very serious and very negative.

That's a lot of weight on one man's shoulders.

Well, he ran for the presidency of the United States, so he assumed the responsibility.